1. Field of the Invention
This invention relates to a clamp for attaching recessed lighting fixtures to flanges of inverted T-shaped rails which comprise a grid-type ceiling. The clamp is at least partially excised from the housing of the lighting fixture.
2. Description of the Prior Art
In the prior art, recessed fluorescent lighting fixtures are mounted on the flanges of inverted T-shaped rails forming a part of a grid-type ceiling. However, such an arrangement requires some means to inhibit the fixture from falling if the T-rails or fixtures shift. This is of particular concern in the event of an earthquake. It is a requirement of the National Electrical Code that such a means be provided.
Typically, this requirement is met by attaching grid clips in the field to secure the fluorescent lighting fixture to the T-rails. However, this procedure is awkward and requires the worker to carry a supply of clips to the job site.
The apparatus of U.S. Pat. No. 4,356,537 to Stahlhut et al. eliminates the need for grid clips by including a retainer hook in the fixture positioned at a right angle (90.degree.) to the fixture so as to engage the T-rail. However, this retainer hook does not prevent longitudinal movement of the lighting fixture along the T-rail. Therefore, this apparatus is deficient in preventing dangerous movement of the fluorescent lighting fixture in the event of an earthquake or any other event which would affect the level position of the T-rails.